Sutures are used in a wide variety of applications including closing ruptured or incized tissues, soft tissue attachment, anastamosis, attachment of grafts and mesh, etc. Conventionally, to suture ruptured or incized tissues, for example, a surgeon passes the pointed tip of a curved suturing needle with thread or suture attached to the blunt end of the needle through the tissues to be sutured until the tip of the needle penetrates the tissues to span the incision with the needle. Then, the surgeon grasps the tip of the needle which has been forced through the tissues with fingers or a needle holder and pulls the needle through the tissues, the suture following the curved path of the needle. Usually a knot or button is present at the trailing end of the suture to anchor the first stitch. After the surgeon has pulled the suture entirely through the tissues to tension the first stitch, he or she then forces the tip of the needle through the tissues at a location spaced along the incision from the first stitch until the needle again spans the incision. Again, he grasps the tip of the needle which has been forced through the tissues, applies tension to the needle pulls the entire suture through the tissues to complete the second stitch. This process is repeated again and again, with the surgeon tensioning the suture after each stitch to draw the tissues together thereby creating a running or continuous stitch, composed of individual thread loops, which extends the entire length of the incision or rupture.
Needless to say, such suturing by hand is a tedious and time consuming task. Moreover, it involves the repeated handling of the pointed needle, often in very close quarters. In many cases, this results in the needle penetrating the surgeon's gloves raising the possibility of infection for the patient and/or the surgeon.
To address these problems, some suturing instruments have been designed which are supposed to facilitate the manipulation of the suturing needle during the suturing process. See, for example, U.S. Pat. Nos. 2,959,172; 4,109,658; 4,345,601 and 4,557,265. However, to applicants' knowledge, such instruments are not in widespread use. Some of them are unduly complicated and, therefore, expensive. Other prior instruments are relatively difficult to use and are, therefore, not suitable for suturing of a delicate nature and/or in close quarters. For example, the instrument disclosed in the last-mentioned patent above has to be held sideways relative to the direction of the incision being closed. Some of the prior suturing devices suffer also because they do not maintain positive control over the suturing needle and thread during the suturing process. This can result in a non-uniform suture having overly loose and/or overly tight stitches which can cause excessive bleading and/or tearing of tissue.
In general, the prior instruments of this general type are seriously disadvantaged because they do not emulate the manual suturing techniques preferred by surgeons that enable the surgeons to "tailor" each suture to the particular situation and they do not even attempt to handle or manage the thread during the suturing process so as to optimize that process.